Impulse-starter coupling for magnetos



V. W. KLIESRATH AND R. KNOPP.

IMPULSE STARTER COU'VPLING FOR MAGNETOS. APPLlcAloN FILED MAY 31, 19z9.

1,365,700. Patented Jan.18,19z1.

3 SHEETS-SHEET l.

-L A `5 met@ k2 ATTORN'C) a V. W. KLiESRATH AND R. KNOPPa IMPULSE STARTER COUPLING FDR MAGNETOS.`

APPLICATION FILED MA1/31, |919. Y

Ptnwd Jan. 1s, 1921.

3 SHEETS-*SHEET 2.

V. w. KLIESRATH AND R. KNUPP. rMPuLsE STARTER comme ma mAsNEms.

APPLICATION FILED MAY 31| 9|9. 1,365,700. v Patented Jan. 18, 1921;y

3 SHEE`IS--SHEET 3.

i UNITED STATES PATENT OFFICE;

VICTOR w. KLTESRATH, OP EAST ORANGE, AND RUDOLPH RNOPP, OP MONTCLAIR,

NEW JERSEY, ASSIGNORS To THE STMMS MAGNETO COMPANY, OE EAST ORANGE, NEW JERSEY, A CORPORATION or NEW JERSEY.

IMPULsE-sTARTER eoUPLiNG FOR MAGNETOS.

Application filed May 31,

To all whom it may cola-cern.' l

Be it known that we, Vlc'ron W. KunsnATi-r, a citizen of the United States, and RUDoLrH KNoPr, a citizen of Austria, residing, respectively, at East Orange, in the county of .Essex and State,- of New Jersey, and Montclair, in said county and State, have invented certain new and useful lmprovements in ImpulseStarter Couplings for Magnetos; and we do hereby declare the following to be a full, clear, and exact. description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention consists in the novel fea. tures hereinafter described, reference being had to the accompanying drawings which` illustrate one embodimentv of the invention selected by us for purposes of illustration, and the said invention is fully disclosed in the following description and claims.

The object of our invention is to provide a coupling to be interposed between the rotary armature shaft of a magneto generator, and its driving shaft, by which the necessary lspeed of rotary movement will be imparted to the magneto-armature to insure a hot or fat spark for ignition purposes in connection with anl internal combustion engine, although the speed of rotation of the driving shaft may be considerably lower than the. necessary speed of rotary movement of the magneto armature to accomplish this result. This is particularly important in starting the engine, in. order to insure that the first revolutions thereof will be accompanied by hot sparks from the magneto or generatorv in order to insure the ignition of thel eXplosive charges in the eylinders,-and also during they running of the engine when the speed of the engine falls below a predeterminedspeed necessary to drive the magneto armature directly at the requisite speed of rotation. To this end means are provided for locking the driven member of the coupling and the rmagneto armature shaft With which it is rigidly connected against movement and providing a spring between the driving and driven members of the coupling-which is compressed by therotation of the driving member while the driven V Specification 0f Letters Patent.

Patented Jan. 18, i921. 1919. Serial No. 301.129.

member is locked, suitable cam mechanism being provided to release the driven member v and permit the spring to impart the desired rapid movement in a rotary direction to the driven member and armature shaft, regardless Of the speed of rotation ofi the' driving member, the locking mechanisnibeing controlled by centrifugal force so that when the driving member has attained, or is operating at or above a predetermined speed of rotation, the locking mechanism will be held out of operation andthe driving and driven members will rotate at the same speed. Our invention comprises. an improved. impulse starter coupling for the accomplishment of this and other objects, as hereinafter more fully set forth and comprises among other features, an improved form of torsional spiral spring, which is so formed, tempered, and set, that when in unconfined orexpanded condition, successive portions throughout its length are curved about different centers located preferably within the innermost coil, and in different positions radially with respect to the center of the innermost curved portionof the inner coil, the form of the spring and the location ofsaid centers being such that when the spring is vwound or compressed torsionally into position the coils will be brought into substantially concentric relation, and the further compression and expansion of the s ring torsionally cannever have the eifect orendering the coils eccentric, or bringing any coil thereof. into frictional contact with another coil. Bythe employment of this novel' form of Spring in the coupling herein described, extremely advantageous and novel results are obtained in the operation of the coupling, which may be briefly summarized as follows, `to witz-During the relative I movement of the driving member with re` speetto the driven member, at which time the spring is torsionally woundand compressed, the coils are prevented from coming 'into contact, as do the/coils of the ordinary spiral spring, (in which the coils; are originally formed concentrically and are moved into eccentric and contacting relation by winding) so that every part of the spring is subjected tO the same degree of bending and;

. the full elasticity of the spring isn obtained i With which it is used, operator stranded without unduly straining certain parts, more than others and eventually crystallizing the steel of the spring adjacent to the contacting portions, as in the use of the ordinary spring. Again, onthe tripping of the locking mechanism, the full impulse of our entire spring is exerted on the driven member, which is not the case with ordinary springs, and further there is no retarding of lthe spring action, such as is caused by the frictional resistance of contacting coils in the use of ordinary springs, and the driven member is more quickly started and is driven at a greater speed, and' finally our spring is not liable to breakage, which is brought about with great frequency in the use of ordinary springs, and is due to the coils of the ordinary springs being brought into contact by the torsional compression of the spring, inducing both Wear and crystallizw tion, both of which are entirely absent in our improved construction. As the breaking of the spring inr such a. coupling not only puts the magneto out of commission, but also disables the automobile or other engine perhaps leavingthe in a remote place, the importance of this feature of our improved. coupling will be apparent.

Referring to the accompanying drawings which set forth an embodiment of our in.- vention selected by us for purposes of illustration,

Figure l represents a side elevation of our l improved coupling, the position of magneto being indicated in dotted lines, and the drivshaft being broken' away. ,r is a vertical sectional view of'the kleine, the drivingr shaft Vbeing removed.

Fig. 3 is a detail perspective view showing the locking plate, the driven member, the driving member, and other associated parts.

Fig. l is a vertical transverse sectional vienT on the line e-ll of Fig. ffl, looking in the direction of the arrow.

Fig. 5 yis a similar sectional view taken on. the line 5 5 of Fig. 2, and looking in the direction of the arrow.

Fig. 6 is a view similar to Fig. 5 illustrating the operation of one of the cams on the driving member in disengaging one of the locking devices carried by the driven shaft.

Fig. 7 is a similar vievy showing the normal position of the locking levers when the parte are operating at normal speed, and said levers are held out of operative posi tion by centrifugal force. l

Fig. 8 is a detail view of a spiral spring which we prefer to employ in. our improved coupling, as' it appears after being formed, tempered, and set, and before being placed under com pression,

of manufacture,

I hub von the side of the pivot positions lng rotated at suiiicient adapted for In the accompanying dravvings l represents a stationary plate cfa-ny desired form,

provided vwith means, as screws for example,

by which it may be secured rigidly tov the frame of a magneto, indicated at M, in dotted lines in Figs. l. and 2, the said plate being provided with a central aperture through which the shaft of the magneto armature, indicated at m in Fig.v 2, may pass. This stationary plate 'l is preferably provided 'with an outwardly extending dust flange, indi. cated at 2, and is al@ provided with an annular locking hub, indicated 'at 4, provided with a locking shoulder 5. For` convenience We prefer to vprovide the locking plate l with a thin. plate or stamping 3, carrying the annular dust flange 2, and to make the hub et separate from the plate and attach the hub Ll, plate 3, and plate l, togetherv by means of rivets, one of which is indicated at 6 in Fig. 2, or otherwise, but We do not limit ourselves to this construction. The plate l is shown provided with screws, indicated in dotted lines at 7 for attaching it to the frame of the magneto, and it willbe seen that the armature shaft m, Which is preferably provided with a tapered portion, and an ex- `terior threaded portion, projects through theV central apertures in the plates 1 and 3 and 4. 'The driven mem r of our improved :oupling comprises a disk 8 having avcentral sleeve 9 projecting on both sides ofthe same, the inner end of the sleeve 9 being preferably tapered to fit the tapering portion of the shoulder of the armature shaft'm, and provided with a keyway l() to receive a key (not shown) for rigidly securing it to the armature shaft.

On its inner face the disk 8 carries a pair of 'pivoted centrifugally controlled locking levers 11--1l, pivoted at 12--12 to 'the disk S. Each of these levers i's provided With a locking detent 13 located on one side of its on the other side of its pivot, and each of said levers is provided with'an extension l5 adjacent to the detent and projecting'beyond the detent, increasing the length of the lever on that side of `its point of pivoting, said extensions 15--15 acting as centrifugal Weights to Withdraw the locking levers to their inoperative whenever the armainuev shaft is be# or predetermined speed, to vproduce the desired spark. 'We prefer to construct the levers in substantially the manner described'with the Weighted ends orv exten *ons projecting beyond the locking detente and located at the opposite ends of the lever from their cam engaging portions la. Une advantage of this construction is that by varying the length of the projecting portions l5, the coupling may be readily use under circumstaiues respiral spring When stantially the form shoivn in Fig. 8, and when given its required tension, it will assume substantially the formof an ordinary Further compression lize, and can at all times exercise its maximum resiliency with the result of securing the highest possible speed of rotation. In other Words, Whereas increased tension tends to distort the coils of an ordinary spiral spring out of concentric relation and force the coils into contact improved spring is so constructed that increased tension tends to force its coils into a concentric relation which they do not have v when formed, set, and tempered.

inearly cylindrical. recess I videdbinx the stop lug For convenience 1n inserting the spring 25, We conveniently roll up the ends of the spring to form the cylindrical retaining portions ,QG-Q'L which are connected respectively to the driving member 20 and the -driven member 8. We prefer to form a Q8 in the lsleeve 21 ofi the driving member, to receive the end 26 of thespring, and a similar recess 29 is pro- 16 of lthe dislr 8 to receive `the other end 27 of the spring, as clearly shown in Fig. 4. When the parts are assembled, as shown in Fig. 4, the normal tension of the spring tends to hold the stop lug 16 of the driven member or dish 8 in contact Avvith the stop lugrl 23 of the driving ment ber 20. In assembling the parts, the cut off segments formingV the straight sides 17-17 of the disk 8 permit the dislr to beinserted Within the housing 22 past the opposite cams 2li-#24, as indicated in Fig. 5, and to pass beyond these cams which are in the same plane as the locking levers 11.

In assembling the parts a Jfelt washer 3l) (see Fig. 2) is inserted Within the dust flange 2, and a dust ring, indicated at 3l Fig. 2, is pressed on a reduced portion 22a of the housing 22, to engage the Washer 3G within the dust flange 2, thus eectually sealing the device against `the 4ingress of dust. or other extraneous matter. he

parts can be held in operative relation in any desired manner. In the present in-` stance We have shown a nut 32 screwed on the outer end of the sleeve 9 for holding ithc driving and driven members together', and We have also shown'a hollow sleeve nut 33 screwed on the threaded portion m. for holding the sleeve 9 firmly in engagement f with the conical portion of the armature shaft. The driving member mayy be protempered and set, before' any tension is applied thereto and the several,

centerswill be brought into substantially concentric relation. of our improved spring 25 will continue to with each other, our

Iprovide an intermediate driving ring, i

` with y those f of the a resilient connor pling; which will taire up ing member ZG Wvili the 1,365 ,voo

vided with any suitable means for connecting it with the driving shaft, indicated in Fig. l at 34. In the present instance We have snown the outer face o' the drivi g member or disk 20 provided with a pluraiity 'TE of serrations or projections, indicated at B5, and being preferably twenty in number. Ne have also shown the driving shait, which is ordinarily mounted in axial aline ment with the shaft mof the magneto, pro4 7 5 vided With a driving collar 355, bored to lit the shaft and split, as indicated at 37, and provided with a securing bolt 3S., which preferably passes through the collar and shaft transversely of the split 37 in the col- 8@ lar, so as to clamp the collar on the shaft., as Well as to secure it vtorotate 'tl'ierewith This collar is provided with a fiange p tion 39 o substantially the seme diamei as the driving disli 20, and has its inner far provided With a plurality of serrations or projections a0, one less lin number than number of projections or serrations Se on the dislr 20, in other words, this stance having nine-te in projections. lli/'e l cated at 4i, which is preferably 'madf`I resilient material such as vulcanized i ber, of the desired degree of softness, wvl is provided on its inner `tace with a plurality of serrations er projections 42 of the number as those o' the disk Sill, interengagingthe same, and on its cuter ii ce is provided with" a piurality of serra'tion er rejections El corresponding in num driving coilar T36, and the same. We Afind i inY t" 'on-beta.. .ngmember of the ce i sudden eher. and jars, and it aise provides in elect anat may ibe termed YVernier tyre ci" ai ment, by means ,i magneto with p i so as to bring t engine in prop i sparking positi Assuming that and it engine is rotated by terengaging with cons fuc'tion desi shaft land the drii,

the parte are desired to start the enr hand or by' starter in such direction as to immi ment to thendriving member 20 tion oil the arrows in Figs. understood that the secti these figures viewed rrr rections. The driven member armature shaft 'm wviil be locked vment by the engagement ci one ing levers ll with the locking shown in Fig. 5; The rotation o i. 't

ing the inner end the the direction or the arrow increase the tension cfr 'the quiring the maintenance of different magneto speeds without varying any other portion of the apparatus. ln the accompanying drawings we have shown our invention applied to a coupling intended for use with a magneto producing two sparks per revolution of the armature shaft, and as will be readily understood, either one of the locking levers 11 may engage the locking shoulder yof the locking hub 4, said shoulder being located onr the upper side of the hub, so that the disk 8, and the armature shaft m with which it is rigidly-connected, may be locked in two positions at opposite points inthe revolution thereof. The disk 8 is also provided on its outer face with a stop lug or projection 16, and segmental portions of said disk on opposite sides of the center are cut away, as indicated at'iT-l'?, to facilitate may be formed separately and secured there- 1 to, which housing extends within the annular recess formed by the dust flange 2 (see Fig. 2). On its inner face the, disk 20 is also provided with a stop lug 23 for engaging the stop lug 16 on the driven disk 8, and the driving disk 20 is also provided, in this instance at points diametrically opposite to each other, with cams 24--24, for engaging the ends 14-14 of the locking levers, and

positively withdrawing them from locking y osition with respect to the locking hub 4.

hese cams' 24 may be formed in any desired way, but we find it convenient to formr them 'by indenting portions of the housing 22, vas shown best in Fig. 3. 1

4Between the driving and driven members of the coupling we interpose a spring 25 of peculiar construction, which we have found to be especially desirable for use in this device. In thel formation ofthe ordinary spiral springs, the spring material is coiled about a common center in the form of a helix, or in other words, the coils have -a constantly ini entire length of the spring, and puts certain parts of the spring under greater stress than others, with the result that the highly teni-- pered material rapidly crystallizes, and such springs are continually breaking. ln our iinproved. `impulse starter coupling it is ofi greatest importance that the spring should not breakxfas the result would be to stop the operation of the magneto and the engine with which it is connected, and secondly there must be nothing to inteifere with the rapid motion imparted by the spring, as one of the principal objects of the couplingl is to impart very rapid movement to the armature shaft', and anything which tends to slow this movement effected by the tension of the spring, tends to defeat the operation of the device. f

As a result of much study and experiment we have found that a spring designed substantially as shown in detail in Fig. 8, being substantially eccentric throughout its entire extent and increasing the distance between adjacent coils, produces the most advantageous results in our coupling without any of the difiiculties which have been heretofore experienced in the use' of spiral springs. In.

forming this spring, we take a rod or band (preferably a band) of spring material and bend it into the form shown in'Fig. 8 for example, in which the several coils, substantially three coils being herein shown, are in the same plane, and gradually increase in distance from each other and are bent into curved form, successive portions of each coil Ybeing curved concentrically7 with or about totally different centers disposed in different positions radially with respect to the center of the innermost curved portion of the inner coil. In Fig. 8, for example, arrows are indicated leading fi'om ten different centers in v different directions to portions of the spring f curved'about or concentric therewith.

about or concentric with each of said centers,

as reasonable variations may be made in the same within the limits of our invention, the

essential feature of which is that successive C portions of the spring coils shall be curved concentrically with or about entirely different and distinct centers, substantially as in the manner shown in Fig. 8', so that when the spring is coiled down and placed under its normal tension, every portion o f the spring also cause the stop lug 23 to move away from the stop lug i6 of the driven member. As the rotation of the driving member proceeds one of the cams 24; will be brought into engagement with the end "i4 or" the locking lever ll, in engagement with the locking hubq thereby tripping said lever, as shown in Fig. 6, and releasing the driven member 8 f the coupling, which is then acted upon by the compressed spring 25 to effect a partial rotation at very high speed to the armature shaft, also in the direction oi the arrows in the several figures, until vthe stop lug 16 on the driven member 8 catches up with and engages the stop lug 23 on the driving member 20, thus imparting the necessary high speed to the magneto armature to produce a strong spark 'for ignition purposes. After a half revolution the other lever 11 will engage the locking hub il, locking the ldriven member and armature shaft, when the operation just described is repeatedf This operation is repeated at every hall revolution of the armature shaft until the driving shaft attains a su'liicient speed to cause the weighted ends of the levers ll to be acted upon by centrifugal force so to hold said levers out ot engagement with the looking hub 4 after which the driven member will be rotated at the same speed as, and with, the driving member, the power being transmitted through the spring 25 under its normal compression or tension, said spring acting as a yielding connection. between the driving and driven members under normal high speed conditions. It for any reason the speed of the englne slows down to such a Apoint that the locking levers ll are no longer held out of operation by centrifugal force, the levers will successively engage the locking hub 4 and the armature shaft will be driven by the series of intermittent rapid impulses instead of by steady or continuous rotation, in the same manner as in starting.

fi/'hat we claim and desire to secure by Letters iatent is L combination with rotary driving member, a rotary driven member., means gto permitting a limited relative movement in a rotary direction between said members, a coil sp, g interposed. and held under tension, torsionally, between said members, said spring when in expanded conditionhaving successive portions throughourtI its length curved about different centers, and constructed to maintain its coils at all times in substantie ly concentric relation, and out of contact with each other, when 'under tensioni, in all the relative positions o?? the driving and driven members, whereby siliency of the entire length of the s'L "ing is at all times ei'ective b S'ws driving and driven members, and reitera-ring action due to frictional resistance between the coils is prevented.

2. In asha't coupling, the combination with a rotary driving member, and a coaxial driven member, and means for permitting a limited relative movement in a rotary direction between said members, of a coil spring interposed and held under tension torsionally between said members, said spring when in expanded condition having successive portions curved about different centers, disposedin different radial directions from the center of the innermost curved portion of the coil, and when under tension maintaining its coils in substantially concentric relation, and out of contact withreach other throughout the entire length of the spring at all times in all relative positions of the driving and driven members, means for locking the driven member, and releasing means for said locking means, whereby the spring is uniformly compressed and the resiliency of the entire length of the spring is at all times eli'ectively exerted between the driven and driving members, and retarding frictional contact between adjacent Coils is prevented` ln a shaft coupling ithe combination with a stationary member provided with a locking shoulder` oi a rotatably driven member, a centrifugally controlled locking lever pivotally connected to the driilenvmember, and .provided with a cam engaging releasing arm, a rotatable driving member, a spring interposed between said driven and `driving members, said spring when in expanded condition having successive portions thereof throughout its length curved about different centers, disposed eccentrioally with respect to each other, interengaging stops on said driven and driving members, normally holding said spring under com ression with its coils insubstantial paral elism, and said -centers of its said successive curved p0rtionssubstantially concentric with the axes of the driving and driven members, and a cam located on. said driving member for engaging the releasing ,arm of said locking lever. l

4. In a shaft coupling the combination with a stationary part provided with a locking shoulderand having an annular dust flange surrounding said looking shoulder, or' a driven mei'uliier. rotatably mountedwith respect to said stationary member, concentric with 'said dust iiange, a centrifugally controlied locking lever pivoted t0 said driveny member and provided with a locking .detent, and with a releasing arm, a rotatablev idriving member mounted concentrically fith respectl to the driven member, a collV spring interposed between said driven and l ves, inter-enga 'ng stopsnon 'lo driving mem Mrs, normally in spring under. compression, a

Cil

. driving member andeaid locking housing cnnected with s'yad 'driving inember., and extending within the dust ange on sind stationary member, and iiiclosing the ii cani 0n said housing for engaging the releasing arm of the locking evei, a dust excluding washer located between the dust shoulder, u

mamon r I i A l a i'lange and said housing, anni a retaining ring surrounding said housing and engaging said Washer. 1

In 'testimony whereof We aix' om' signat'iiies.

VICTOR W. KLIESRATH. RUDOLPH KNOPP. 

